CA1050251A - Method of forming a roller cage - Google Patents

Method of forming a roller cage

Info

Publication number
CA1050251A
CA1050251A CA259,211A CA259211A CA1050251A CA 1050251 A CA1050251 A CA 1050251A CA 259211 A CA259211 A CA 259211A CA 1050251 A CA1050251 A CA 1050251A
Authority
CA
Canada
Prior art keywords
ridges
strip
pockets
forming
cage
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
CA259,211A
Other languages
French (fr)
Inventor
Frank J. Serasio
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Timken US LLC
Original Assignee
Torrington Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Torrington Co filed Critical Torrington Co
Application granted granted Critical
Publication of CA1050251A publication Critical patent/CA1050251A/en
Expired legal-status Critical Current

Links

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16CSHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C33/00Parts of bearings; Special methods for making bearings or parts thereof
    • F16C33/30Parts of ball or roller bearings
    • F16C33/46Cages for rollers or needles
    • F16C33/54Cages for rollers or needles made from wire, strips, or sheet metal
    • F16C33/542Cages for rollers or needles made from wire, strips, or sheet metal made from sheet metal
    • F16C33/543Cages for rollers or needles made from wire, strips, or sheet metal made from sheet metal from a single part
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D53/00Making other particular articles
    • B21D53/10Making other particular articles parts of bearings; sleeves; valve seats or the like
    • B21D53/12Making other particular articles parts of bearings; sleeves; valve seats or the like cages for bearings
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16CSHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C19/00Bearings with rolling contact, for exclusively rotary movement
    • F16C19/22Bearings with rolling contact, for exclusively rotary movement with bearing rollers essentially of the same size in one or more circular rows, e.g. needle bearings
    • F16C19/44Needle bearings
    • F16C19/46Needle bearings with one row or needles
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49636Process for making bearing or component thereof
    • Y10T29/49643Rotary bearing
    • Y10T29/49679Anti-friction bearing or component thereof
    • Y10T29/49691Cage making

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Rolling Contact Bearings (AREA)
  • Shafts, Cranks, Connecting Bars, And Related Bearings (AREA)

Abstract

METHOD OF FORMING A ROLLER CAGE
ABSTRACT OF THE DISCLOSURE
Ridges are preferably rolled-formed into a long, flat metal strip; and pockets are also formed in the strip with their axes perpendicular to the ridges. The ridges are then flattened to form lateral projections extending into the pockets with the projections serving to retain rolling members placed in the pockets. A predetermined length of the metal strip is wrapped into an annular shape to form the cage.

Description

' ~0~02S~

SPECIFICATION
This invention relates to antifriction be~rings. More particularly, this invention is a new method of forming an antifriction bearing cage.
A particular advantage of th'is new method is that a long strip of metal may be formed with laterally separated longitudinal ridges above at least one surface of the strip. -A similar ridge or ridges may also be raised above the opposite surface of the strip if this is desirable or necessary for the particular cages to be formed from that strip. The ridges are preferably roller formed but may be stamped or pressed if desired. Side flanges may be formed on the metal strip at the same time the ridges are formed or at another time, if such flanges are desired on the finished cage. The strip may either be stored for future use or used immediately for the manufactllre of a large number of bearing cages which are all equal in axial length of cage but which may ha~e ~', different diameters and different bearing roller pockets sizes. Roller pockets are formed in the strip preferably by piercing, with the pockets having their axes perpendicular to the ridges. Preferably, the ridges are formed before the pockets are pierced, but under some circumstances it may be ~, desirable to'form the pockets before forming the ridges.
After the ridges and the roller pockets are made, the ridges are ~lattened down by rolling or pressing. This flattenning causes material from the ridges to be flowed or ~ormed or extruded into projectio~s or tabs extending into each lateral side of the roller pockets near the surface of the strip on which the ridges had been formed. These projec-tions are used to retain bearing rolling members placed in ~0502S~
the pockets in the cage, with the lateral pocket width being slightly less than the roller diameter. While the ridges are being flattened, it may be necessary to restrain the sides of the flat strip against sideways movement, thus assuring that the projections from the ridges will be formed into the pockets and that the ridges will not just spread sideways forming a wider flat strip without causing the projections to form.
After the projections are formed, a predetermined length of the metal strip is cut and then wrapped into an annular shape. The circumferential ends of the strip are connected together by any appropriate means such as welding to form the bearing cage. For some cages, those ends are left free and unattached, Bearing rollers are pressed past the projections into the roller pockets or are inserted from the opposite side and are retained in the pocketq by the ' projections.
According to a broad aspect of the present invention, there is provided a method of forming a cage for a bearing comprising as part of a series of steps: forming laterally separated longitudinal ridges on at least onè flat side of a metal strip, and rectangular pockets having their long sides perpendicular to the ridges, flattening the ridges to form pro-;~! jections extending into the pockets, and cutting off a prede-termined length of strip.
The invention, as well as its many advantages will be further understood by reference to the following detailed des-cription and drawings in which:
Fig. 1 is a perspective view showing a portion of a long metal strip from which a cage is to be made by our new method, ~

~ E3 1~S02S~
Fig. 2 is a perspective view showing the strip of Fig. 1 after a pair of lateral ridges have been rolled-formed in the metal strip, Fig. 3 is a perspective view showing the strip after the ridges have been formed and the pockets have also been formed, Fig. 4 is a perspective view showing the strip after ~ .
.~

;~
.

:~
- 2a -B

lOSQ~

the ridges have been flattened to form the projections;
Fig. 5 is a sectional view taken along lines 5--S of ~? ig. 4;
Fig, 6 is a side elevational view showing the final cage after the metal strip is wrapped up and welded;
Fig. 7 is a perspective view showing a metal strip -having a pair of laterally spaced ridges rolled-formed on both flat sides of the strip;
Fig. 8 is a perspective view showing the strip of Fig.
7 after the pockets have been formed in the strip;
Fig. 9 is a perspective view illustrating the cage formed a~ter the strip of Fig. 8 has had the ridges flattened to form projections on both the upper and lower sides of the , aage bars and the strip has been rolled into an annular ~hape7 Fig. 10 is a sectional view of a thinner cage;
Fig. 11 is a sectional view of a cage made of the same strip as the cage of Fig. lO but with the strip wrapped up ', in the opposite curvature;
Fig. 12 is a perspective view showing a strip similar to the strip of Fig. 3 but with the addition of side flanges;
and Fig. 13 is a perspective view showing the cage made `~ from the wrapped up and welded strip of Fig. 12.
Like parts in the various figures will be referred to by like numbers.
Referring to the figures and particularl~ to Fig. 1, the long, flat metal strip or plate lO represents a portion of a long metal strip from which ~he bearing cage is to be formed. The strip r~ay be relat:ively thick, that is greater ~, ~OS(~2S~

than half the roller diameter, or relatively thin, that is less than half the roller diameter.
~ he pair of laterally spaced ridges 12 and 14 have been for~ed on the plate 10 (Fig. 2~ preferably by a rolled-formed process. These ridges, however, can also be formedby pressing or stamping. They are not formed hy machining, which removes metal.
The metal strip 10 with the laterally spaced ridges 12 and 14 is then pierced to form the rectangular pockets 16 as shown in Fig. 3. The long sides of the rectangular pockets 16 are perpendicular to the ridges 12 and 14. Preferably, the ridges 12 and 14 are formed before the pockets are pierced into the strip; however, if desired these steps may be reversed.
The piercing of the pockets 16 into the strip 10 resul~s in a long metal strip having end rims 18 and 20 which are interconnected by the crossbars 22 containing the ridges 12 and 14.
~ The laterally separated ridges 12 and 14 are thereafter - 20 flattened to form the lateral projections 24 and 26 shown in Fig. 4. The lateral projections 24 and 26 are at the top surface of the crossbars 22 and each extend laterally into the pockets 16. While the ridges 12 and 14 are being flat-tened, the strip 10 may be held laterally by any well-known means to insure that the pressure exerted against the ridges 12 and 14 causes the ridges to be extruded into the pockets 16. l The long, flat strip may then be cut to a predetermined length, wrapped into an annular shape, and welded or mechanically joined or bonded by other well-known means to form the cage ~OS02S~l shown in Fig. 6. If desired, the cage may be formed with the circumferential ends left free and unattached. The cage includes the end rims 18 and 20 interconnected by crossbars 22 with the end rims and crossbars defining circumferential-ly separated pockets 16. The projections 24 and 26 which extend into the pockets 16 from the radially outside surface of the crossbars 22 will serve to prevent any rollers placed ln the pockets 16 from falling outwardly from the pockets. In some cases where it is desired to use the projections to prevent the rollers from falling inwardly, as where the cage is used to hold rollers within an outer race or needle bearing cùp, the strip will be wrapped up with projections, such as projection 27, at the inner surface of the cage as in Fig. 11.
If desired, a comparatively heavy wall with projections ; near the outside surface as in Fig. 5 to prevent the rollers ; from falling outwardly, may be provided: but with the radial-ly inner edges of the pockets as pierced preventing the rollers from falling inwardly from the cage. The wrapping up of the strip causes these inner edges to draw close enough together to reduce the pocket opening at this inner surface to less than the roller diameter.
As shown in Fig. 7, a second pair of laterally spaced ridges 28 and 30 may be formed on the other surface or bottom surface of the long, flat metal strip 10. Ridges 28 and 30 are also laterally spaced from the rid~es 12 and 14 formed on the top surface of the metal strip 10. ~idges 28 and 3Q are also preferabl~ rolled-formed, but may be pressed - or stamped.
Fig. 8 shows the long metal strip of Fig. 7 after the ~0~i~251 pockets 16 have been pierced through the metal strip to form the rims 18 and 20 interconnected by the spaced crossbars 22 forming the rectangular pockets 16 with the long sides of the rectangular pockets being perpendicular to the ridges.
As with the embodiment of Figs. 2 through 6, the ridges are preferably formed before the pockets, but if desired, the pockets may be formed before the ridges.
The ridges 12 and 14 on the top surface of the strip 10 and the ridges 28 and 30 on the bottom surface of the strip lO are then flattened while the lateral sides of the metal strip are held against lateral movement, to form projections extending laterally into the pockets 16 from both the top surface of the crossbars 22 and the bottom surface of the crossbars 22. The metal strip is then cut to the predeter-mined length, wrapped into an annular shape, and then weldedor otherwise bonded to form the cage shown in Fig. 9. This cage includes end rims 18 and 20 and crossbars 22 which define circumferentially spaced pockets 16. In addition to the projections 24 and 26, extending laterally into the ; 20 pockets 16 from the radial outside of the crossbars 22, the lateral projections 32 and 34 formed when the ridges 28 and 30 of Fig. 8 were flattened extend into the pockets 16 from the radial inside of crossbars 22. These lateral projections 32 and 34 prevent a roller placed in the pockets 16 from falling inwardly. Thus, the cage shown in Fig. 9 may be used to prevent both inward and outward falling of the ~ollers from pockets 16.
While the preferred number of ridges on each surface of the strip is two, it is also practical to have two spaced ridges on one surface and just one ridge on the second , . .

.

~(~502Sl s,~rface spaced laterally between the two ridges on the first surface. Similarly, it is possible and practical to form more than two ridges on either or both surfaces, with projections from all the ridges extending into the roller pockets.
The invention is also used in linear bearing assemblies where plain reciprocating linear motion, as in machine guideways, is involved. In this case, of course, the strip ~-remains straight and is not wrapped up into an annular cage.
If it is only desired to retain rollexs in one direction, the strip of Fig. 5 may be used.
It is not necessary that the ridges be flattened down to the flat surface of the strip, but only that they be flat-tened enough to produce the desired roller-retention projec-tions in the roller pockets. Indeed, flattening down flushto the flat surface would be difficult.
Fig. 10 shows a cross-section of a cage made from the same s~rip as the cage of Fig. 11 but with the strip wrapped around in the opposite direction so that the rollers are pre~ented from falling radially outwardly by projections 35.
Fig. 12 is a perspective view of a strip with formed ridges and roller pockets similar to the strip of Fig. 3 but with the added feature of side flanges 36 and 38 formed perpendicular to the strip at each lateral side. If a particular cage required it, only one such side flange would be formed on the strip. The wrapped up annular cage made from this strip is shown in perspective in Fig. 13 with the flanges directed radially inward. Similarly, the cage could be formed with the flanges directed radially outwardly.
.

~SO~Sl Each cage could have the roller retention formed at either surface as desired.

Claims (9)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A method of forming a cage for a bearing comprising as part of a series of steps: forming laterally separated longitudinal ridges on at least one flat side of a metal strip, and rectangular pockets having their long sides perpendicular to said ridges, flattening the ridges to form projections extending into the pockets; and cutting off a predetermined length of strip.
2. The method of Claim 1 wherein the sequence of steps comprises: first, forming the laterally separated longitudinal ridges; then forming the rectangular pockets;
then flattening the ridges to form the projections; and then cutting off the predetermined length of strip.
3. The method of Claim 1 wherein the sequence of steps comprises: first, forming the laterally separated longitudinal ridges; then cutting of the predetermined length of strip; then forming the rectangular pockets; and then flattening the ridges to form the projections.
4. The method of Claim 1 wherein the sequence of steps comprises: first, forming the rectangular pockets; then forming the laterally separated longitudinal ridges; then flattening the ridges to form the projections; and then cutting off the predetermined length of strip.
5. The method of Claim 1 wherein the sequence of steps comprises: first, forming the rectangular pockets; then forming the laterally separated longitudinal ridges; then cutting off the predetermined length of strip; and then flattening the ridges to form the projections.
6. A method of forming a cage for a rolling member bearing comprising as part of a series of steps: forming laterally separated longitudinal ridges on at least one flat side of a metal strip, and rectangular pockets having their long sides perpendicular to said ridges; flattening the ridges to form projections extending into the pockets for retaining rolling members placed in the pockets; and wrapping a predetermined length of strip into a substantially annular member.
7. The method of forming a bearing cage in accordance with Claim 6 wherein the ridges are rolled formed.
8. The method of forming a bearing cage in accordance with Claim 6 wherein at least one flange is formed on one longitudinal side of the metal strip.
9. The method of forming a bearing cage in accordance with Claim 7 wherein a first pair of ridges is rolled formed on one flat side of the metal strip and a second pair of ridges is rolled formed on the other flat side of the metal strip; and both pairs of ridges are flattened to form projections for retaining rolling members placed in the pockets.
CA259,211A 1975-09-22 1976-08-16 Method of forming a roller cage Expired CA1050251A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US05/615,408 US3992764A (en) 1975-09-22 1975-09-22 Method of forming a roller cage

Publications (1)

Publication Number Publication Date
CA1050251A true CA1050251A (en) 1979-03-13

Family

ID=24465244

Family Applications (1)

Application Number Title Priority Date Filing Date
CA259,211A Expired CA1050251A (en) 1975-09-22 1976-08-16 Method of forming a roller cage

Country Status (9)

Country Link
US (1) US3992764A (en)
JP (1) JPS5242459A (en)
BR (1) BR7606211A (en)
CA (1) CA1050251A (en)
DE (1) DE2641918A1 (en)
ES (1) ES451705A1 (en)
FR (1) FR2324936A1 (en)
GB (1) GB1533135A (en)
IT (1) IT1068345B (en)

Families Citing this family (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5999121A (en) * 1982-11-09 1984-06-07 エス・カ−・エフ・ク−ゲルラ−ゲル・フアブリケン・ゲ−エムベ−ハ− Cage for roller bearing
DE3344780A1 (en) * 1983-12-10 1985-06-20 SKF GmbH, 8720 Schweinfurt Method and device for the production of profile cages
JPS61146622U (en) * 1985-03-05 1986-09-10
DE3543364A1 (en) * 1985-12-07 1987-06-11 Schaeffler Waelzlager Kg RADIAL ROLLER BEARING CAGE FOR CYLINDRICAL ROLLER BODIES
DE3936451A1 (en) * 1989-11-02 1991-05-08 Skf Gmbh ROLLING BEARING CAGE
US5189791A (en) * 1990-09-20 1993-03-02 The Torrington Company Method for making a retainer having enhanced roller retention
US5070976A (en) * 1990-12-27 1991-12-10 Dana Corporation Sprag retainer
US5410809A (en) * 1993-03-30 1995-05-02 The Torrington Company Method of making a bearing cage with depressed slot end
JPH07127646A (en) * 1993-10-29 1995-05-16 Ntn Corp Retainer for roller bearing
US6330748B1 (en) * 1997-01-24 2001-12-18 INA Wälzlager Schaeffler oHG Method of making formed bodies
DE19740435A1 (en) * 1997-09-15 1999-03-18 Schaeffler Waelzlager Ohg Method for manufacturing rolling element bearing cages from thin-walled strip
DE19754836A1 (en) * 1997-12-10 1999-06-17 Schaeffler Waelzlager Ohg Needle bearing cage and process for its manufacture
DE10126217A1 (en) * 2001-05-30 2002-12-05 Ina Schaeffler Kg Rolling bearing cage
JP2007182987A (en) * 2005-12-07 2007-07-19 Nabtesco Corp Differential oscillating type reduction gear, manufacturing process of differential oscillating type reduction gear, reduction gear and roller bearing
DE102009031722A1 (en) 2009-07-04 2011-01-05 Schaeffler Technologies Gmbh & Co. Kg Cage for a ball bearing and method of making the cage
DE102009032628A1 (en) * 2009-07-10 2011-01-13 Schaeffler Technologies Gmbh & Co. Kg Cage, rolling bearing with the cage and method
DE102013225987B3 (en) * 2013-12-16 2015-08-06 MTU Aero Engines AG Method for producing a cylindrical component, housing and turbomachine
DE102019201565A1 (en) 2019-02-07 2020-08-13 Aktiebolaget Skf Bearing cage segment with an abutting edge in the area of a web to be formed
DE102019201560A1 (en) 2019-02-07 2020-08-13 Aktiebolaget Skf Bearing cage segment with abutting edge for welding
DE102019201564A1 (en) * 2019-02-07 2020-08-13 Aktiebolaget Skf Bearing cage segment with at least one recess for easier bending
DE102021206285A1 (en) 2021-06-18 2022-12-22 Aktiebolaget Skf Cage segment for a roller bearing cage

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR68922E (en) * 1955-09-28 1958-07-23 Ind Schaeffler O H G Fa Cage for roller bearings and especially for needle bearings
FR1142642A (en) * 1956-02-10 1957-09-20 Roulements A Aiguilles Sa Needle stopper and devices comprising such a stopper
FR1171809A (en) * 1956-04-24 1959-01-30 Schaeffler Ohg Industriewerk Process for manufacturing roller bearing cages, in particular for needle bearings with guidance and maintenance of the rollers by the arms
FR1344995A (en) * 1962-10-08 1963-12-06 Riv Officine Di Villar Perosa Method and device for the manufacture of cages for roller or needle bearings
DE1452703B2 (en) * 1963-11-02 1972-05-10 Industriewerk Schaeffler Ohg, 8522 Herzogenaurach METHOD OF MANUFACTURING A RADIAL CAGE FOR CYLINDRICAL ROLLED BODIES
DE1425039C3 (en) * 1963-11-02 1980-01-31 Industriewerk Schaeffler Ohg, 8522 Herzogenaurach Cage for cylindrical rolling elements
US3535964A (en) * 1967-01-06 1970-10-27 Torrington Co Apparatus for forming bearing retainers
FR1470088A (en) * 1967-04-21 1967-02-17 Torrington Mfg Co Manufacturing process for bearing cages
US3526026A (en) * 1967-10-30 1970-09-01 Henry T Warchol Method of making a cage for a tapered roller bearing
FR2040892A5 (en) * 1969-04-16 1971-01-22 Skf Svenska Kullagerfab Ab Stamping ball races from flat metallic - strip
US3878705A (en) * 1972-05-01 1975-04-22 Roger L Iffland Bearing cage and method for producing a bearing cage
US3940193A (en) * 1973-05-03 1976-02-24 General Motors Corporation Roller bearing separator

Also Published As

Publication number Publication date
DE2641918A1 (en) 1977-03-24
JPS5523694B2 (en) 1980-06-24
FR2324936A1 (en) 1977-04-15
JPS5242459A (en) 1977-04-02
GB1533135A (en) 1978-11-22
BR7606211A (en) 1977-06-14
ES451705A1 (en) 1978-01-01
IT1068345B (en) 1985-03-21
US3992764A (en) 1976-11-23

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